To the Editor: The Clinical Trial of Reviparin
and Metabolic Modulation in Acute Myocardial Infarction Treatment Evaluation
(CREATE)1 concludes that, in patients with
acute ST-elevation myocardial infarction (STEMI), reviparin reduces overall
mortality and reinfarction at 7 days (P = .005)
and 30 days (P = .001). This is a megatrial
involving 15 570 patients designed to detect a 15% relative risk (RR)
reduction on the composite outcome at 7 days with a power of 93%. Although
this conclusion is correct based on the applied analysis, it is important
to examine the magnitude of the composite mortality reduction. The CREATE
trial is similar to the Facile Interpretation of Statistical Hypotheses (FISH)
trial postulated by Diamond and Kaul.2 The
CREATE trial shows an absolute reduction in the first coprimary composite
outcome at 7 days of 1.4%. Using a Bayesian approach with a noninformative
prior (prior log odds ratio [OR] distribution with mean, 0 and SD, 10), as
the CREATE trial was the first and only trial of this treatment that had been
conducted, the posterior probability for more than 15% benefit is only 41%,
whereas it is 95% for a threshold of benefit of 6%.